Probability distributions consistent with a mixed state

M. A. Nielsen

doi:10.1103/physreva.62.052308

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Probability distributions consistent with a mixed state

M. A. Nielsen

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Abstract

A density matrix $ρ$ may be represented in many different ways as a mixture of pure states, $ρ= \sum_i p_i |ψ_i\ra \la ψ_i|$. This paper characterizes the class of probability distributions $(p_i)$ that may appear in such a decomposition, for a fixed density matrix $ρ$. Several illustrative applications of this result to quantum mechanics and quantum information theory are given.

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M. A. Nielsen. 1999-09-06. Probability distributions consistent with a mixed state. https://doi.org/10.1103/physreva.62.052308

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